Telephone call transmitter



NOV. 6, 1945. T DOWEY 2,388,313

TEL EPHONE CALL TRANSMITTER Filed Jan. 25, 1944 v '7 Sheets-Sheet 1 INVENTOR TL. DOWEV ATTORNEY Nov. 6, 1945. T. 1.. WHY 2,388,313

TELEPHONE CALL TRANZSMITTER Filed Jan. 25', 1944 7 Sheets-Sheet 4 7TL. WEV

A TTORNEV 1945- T. 1.. DOWEY 2,388,313

TELEPHONE CALL TRANSMITTER Filed Jan. 25, 1944 '7 Sheets-Sheet 5 nvveuron TLDOWEY e/ @JQM A T TORNE Y Nov. 6, 1945. T. L. DowEY 2,388,313

TELEPHONE CALL TRANSMITTER Filed Jan. 25, 1944 7 Sheets- Sheet e FIG. /0

ATTORNEY Nov. 6, 1945. 1-. L. DOWEY TELEPHONE CALL TRANSMITTER 7 Sheets-Sheet 7 Filed Jan. 25, 1944 ATTORNEY Patented Nov. 6, 1945 UNITED STATES, PATENT OFFICE TELEPHONE CALL TRANSMITTER Thomas L. Dowey, Summit, N. J assignor to Bell Telephone Laboratories, Incorporated, New York, N. Y., a corporation of New York Application January 25, 1944, Serial No. 519,598

8 Claims. (Cl. 177-380) This invention relates to telephone call transmitters and more specifically to a type'of call transmitter in which code wheels are actuated by the operation of key members for setting a call .with a motor mechanism for moving an alternating generator in direction transverse of the wheels to cause the operation of vibrative reeds between the poles of a magnet for generating signals corresponding to theJsetting of the wheels, the call being indicated prior to the transmitting of the call by dials carried by such wheels.

The object of this invention is the provision of a call transmitter 'of the type above referred to which will be simple in construction, convenient in use and positive in operation. I

In the drawings:

Fig. 1 is an elevation view shown in perspective, the indicating wheels being shown in the operated position;

- Fig. 2 is a right side elevation view shown with the casing partly in vertical longitudinal section taken on line 2- 2 of Fig. 8;

Fig. 3 is a vertical sectional view taken on line 3-4 of Fig. -8 with the keys in normal non-operated position;

Fig. 4 is a View similar to Fig. 3 but showing one of the keys and a number of parts actuated thereby partly operated;

Fig. 5 is a view similar to Figs. 3 and 4 but showing one of the keys and the operated part actuated thereby in full operated position;

Fig. 6 is another view taken on line 3-3 of Fig. '8 but showing the driving mechanism for the alternating current generator in the operated position;

Fig. 7 is a left side elevation view shown with the casing partly in vertical section seen along the line 1-4 of Fig. 8, the operating parts being shown in normal non-operated positions;

Fig. 8 is a top viewshown with thecasing in horizontal sections, showing the generator innormal non-operated position;

Fig. 9 is a horizontal sectional view taken on line 99 of Fig. 6 showing the generator in starting position;

Fig. 10 is a right-side elevation showing the resetting mechanism for the code wheels in the 0perated position;

Fig. 11 is a detail view enlarged showing the code wheels and their actuating mechanism in perspective;

'Figs. 12, l3, 14, 15 and 16 are views of thecode wheels shown in operated position relative to the vibrative reeds of the generator for the transmitting of the signal indicated in-Fig. 1;

Fig. 17 is a partial view showing the clutch elements used in the driving mechanism for the code wheels;

Fig. 18 is a side view of Fig. 17 looking in the direction indicated by the line I8|8 in Fig. 17 and v Fig. 19 is a diagrammatic View of the code wheels developed showing portions of these code wheels in relation to the combination of the vibrative elements of the alternating current generator representing the digits printed on the key.

'The call transmitter of this invention consists "of a base It to which is secured a plate H formed with two upright supports I2 and I3 shown in Figs. 2, 3, 4, 9 and 10. The plate ll at its front disposed "end portion is bent upwardly at right angles to the base 10 and down turned upon itself to form a semicircular edge I4 serving as a com-- mon pivot for a set of manually operable piano shaped key members Kl, K2, K3, K4, K5, K6, K1, K8, K9 and Kit. These keys are held in assembled position on the pivotal edge I4 by respective retractile springs I5 formed in the manner of a comb having it longitudinal edge abutting against a shoulder portion l6 formed by the bending of the plate I I and a small distance from the pivotal edge 14 while the free end of retractile springs 15 thus formed abut with a predetermined normal tension against shoulder portions I1 formed with the respective keys K1, K2, K3, etc. I

The free end portions of key members K1,, K2, K3, etc. extend into guiding slots in a plate LX secured at both ends to lugs LXI and .LX2 formed in uprights I2 and i3 and are formed with camm-ing surfaces'CS of different length terminating in semicircular recesses I 8 shown in Figs. 2, 3,

-4, 5, 6 and 7 serving as stops for limiting the movement of a bar 19 actuated by the camming surfaces CS to movements corresponding to the digit value of the keys. The bar H] which is of circular cross-section is supported at both ends by the arms 20-2011 formed with similar gear sectors 2I2la in turn formin'gthe arms of a U-shaped bar B, mounted for free pivotal movement against the tension of a spring I ona shaft 2-2 journaleda't both ends in the upright supports l2 and 13. Gear sectors 2| and 2la, as shown in Figs. 3, 4, 5, 6, 7 and 11, engage respective gear sector members 23-230. mounted for free rotation on the reduced end portions 25 of a shaft .26. Sector members 2 323a are formed with arms m and ml to which is secured as by welding the ends of a clutch bar 24 of V-shaped cross-section for movement concentric to a plurality of wheels WI, W2, W3, W4, W5, W6 and W1 each having as shown diagrammatically in Fig. 19 a code portion CO representing digits 1 to 9 plus a zero, ratchet teeth RP and a dial portion (110. These wheels are mounted for free rotation on the shaft 25 and are provided with radial longitudinal movable clutch arms 21 having at one of their ends substantially oval-shaped openings OP best seen in Fig. 17 engaging the shaft 25 and their opposite ends are fitted in slots in lugs 29 formed at the periphery of the wheels WI, W2, W3, etc. Longitudinal movements are successively imparted to arms 21 for engaging their V-shaped ends with the bar 24 by theoperation of respectively associated pawl-like members PI, P2, P3, P4, P5, P6 and P1 also mounted for sliding movement on shaft 26 as shown in Figs. 3, 4, 5, 6, l1 and 1'7. These pawl-like members are provided with diametrically opposite arcuated portions P and PL, engaged by a pair of lugs LI carried by the radially slidable arms 21 so as to permit rotary movement of these arms and that of wheels WI, W2, W3, etc. relative to their associated pawl-like members PI, P2, P3, etc. as effected by the engagement of arms 21 with bar 24 under control of any one of the key members KI, K2, K3, etc. as will be hereinafter described in detail.

The successive operation of pawl-like members PI, P2, P3, etc. and therefore the successive longitudinal movement of their associated arms 21 for engaging the bar 24 is eifected by the rotation of a shaft 39, Figs. 3, 4, 5, 6, 7, 8, 9 and 11. This shaft is operated in a clockwise direction by a gear sector 32 engaging a pinion 3I keyed to this shaft the gear sector being itself actuated by a rectractile spring 33 tensioned upon the operation of this gear sector as eifected by a lug L carried by a manually operable sector-shaped plates 35 best seen in Figs. 2 and having a handle 34 extending through a slot SL in a casing IUY cooperating with the base It for housing the transmitter mechanism.

The sector plate 35 and gear sector 32 are pivoted on a common shaft 49 journaled in upright supports I3 and M best seen in Fig. 8 while a pawl 42 pivoted on shaft 26, Figs. 7, 8 and 11, is engaged by a pin PX carried by the arm M of gear sector 23' to be moved against the tension of a retractile spring 42X out of engagement from ratchet wheel 39 keyed on shaft 39 following the return movement of the bar 24 to normal unoperated position shown in Figs. 3, 6 and 7 for permitting the rotation of shaft 39 an angular distance corresponding to one tooth of ratchet wheel 39 in a, manner which will be hereinafter described in detail. Shaft 39 which with the pawl-like members PI, P2, P3, etc. form a transfer mechanism is journaled at both ends in upright supporting plates I2 and I3, and, in addition to pinion 3| and ratchet wheel 39, is provided with ratchet teeth RI, R2, R3, R4, R5, R3 and R1 disposed in staggered or spiral relation thereon corresponding to the number of pawllike members PI, P2, P3, etc. and to the number of teeth of ratchet wheel 39.

According to this mechanism. the movement of sector shaped plate 35 by handle 34 from the position shown in Fig. 2 to the position shown in Fig. 10 is effective to tension a rectractile spring 35m and through lug L carried by the plate 35 operates the gear sector 32 for tensioning its retractile spring 33 while imparting a complete counterclockwise movement to pinion 3I and thereby to shaft 39, while the pawl 42 is held disengaged from the ratchet wheel 39 by the pin PX due to the bar 24 being in normal non-operated position. Upon the return movement of sectorshaped plate 35 and 'the gear sector 32 under the tension of their retractile springs 35s: and 33, the movement of gear sector 32 rotates the shaft 30 in a clockwise direction causing the tooth RI carried by this shaft to engage the pawl-like member PI for moving it downward longitudinally against the tension of retractile spring RS to a point whereby its free end engages the plate II for stopping the rotation of shaft 30 while the longitudinal movement of pawl-like member PI causes its associated clutch arm 2? to engage with the clutch bar 24 thus operatively connecting the wheel WI to the bar 24 which, as above stated, is rotated in position concentric to the wheels WI, W2, W3, etc. by the movement of gear sectors 2323a in engagement with gear sectors 2 I--2 la, the latter being actuated through the different cam portions CS of the keys KI, K2, K3, etc, in engagement with the common bar I9. The pawllike members P2, P3, etc. like pawl-like member PI are normally held by similar retractile springs RS against a ridge element SB in position to be engaged. by their respective teeth RI, R2, R3, etc. on shaft 39, these springs being formed as shown in Figs. 3, 4, 5, 6, 7, 9 and 10 in the manner of a comb having its longitudinal edge clamped to a plate 56 in turn mounted on a pivot 51 and normally held in retracted position by a coil spring 58 having sufficient tension. to collectively flex the springs RS of pawl like members PI, P2, P3, etc. This spring is hooked at one end to upright 59m and at its other end to a lug member 59 formed with the plate 53 disposed transverse of the pawls Pi, P2, P3, etc. and plate 59 is provided at its free edge portion with notches BI serving to guide and hold the free end of pawls PI, P2, P3, etc. in vertical alignment or registry with the teeth RI, R2, etc. on shaft 39, the plate being actuated through the operation of an arm 55! by a cam 59Y mounted for rotation as a unit with a cam 59 on the reduced end portion ep of shaft 39, as shown in Figs. 2 and 10 and actuated by the manual movement of plate 35 in a manner which will be hereinafter described in detail.

Pawls PI, P2, P3, etc. are formed with shoulder portions 62, best seen in Figs. 3, 4 and 5, engaged by the plate 55 for collectively moving these pawls downwardly for disengaging lugs 65 carried thereby from any one of the ratchet teeth R3? of code wheels WI, W2, W3, etc. for permitting the return of the latter to normal unoperated position by the pivotal movement of a bar 45 concentric to shaft 25 upon the manual operation of the sector shaped plate 35 following each call transmitting operation.

The bar 45 is formed with arms 47 and 48 pivoted on the reduced end portions 25 of shaft 26 and extends in engageable relation with similar aligned spokes as SI, of wheels WI, W2, W3, etc. for returning the latter to normal non-operated position through the engagement of a pin 43 carried by arm 48 of bar 45, see Figs. 2, 8, 1d and 11, this pin extending into a slot 44 formed in sector shaped plate 35 so that the manual operation of the latter from the position shown in Fig. 2 to the position shown in Fig. 10 is effective to return the wheels WI, W2, etc. collectively to normal non-operated position but timed to secure following the movement of pawl-like members PI, P2, P3 and thereby the disengagement of lugs 65 from teeth of wheels WI, W2, W3, etc.

The plate 35 as shown in Figs. 2 and 10 is provided with a substantially -V-shaped opening forming paths or tracks TI and T2 for a pin 5| carried by g'ear sector 2Ia. The track T2 as shown-in Fig. 2 is generated-by a radius from the center of shaft Hon-which the gear sectors 2! and 2I'a'are pivoted so as to permit when the plate 35 is-in normal non-operated position the pivotal movement of the sectors 2-I and 2Ia as effected by the operation'of the keys KI,'K2, K3, etc. act,- ing on bar I9, while the track TI serves asa lock for the gear sectors 2| and 2Ia and for the keys KI, K2, K3, etc. upon the movement of .plate 35 from theposit'ion shown in Fig. 2 to the position shown in Fig. 10, while the movement of plate 35 .as above described actuates the gear sector 32 through the lug L carried by this plate for tens'iohing the spring 33 the function of which is to return the gear sector 32 to normal non-operated position and thereby rotating the shaft 35 a complete turn step by step upon the successive operation of key members KI, K2, K3, etc. and the consequent operation of .bar 24 actuatingthe pawl 42 to cause the rotation of'shaft 30 for the successive engagement of ratchet teeth RI, R2, R3,.etc. with their corresponding pawl-like members PI, P2, P3, etc. On shaft 22, as best seen in Figs. 2, 3, 4, 6, 7 and 10, is mounted for freepivotal movement thereon, a plate 55 operated through its engagement with projections EX carried by the key members K2, K3, etc. The functon of this plate is to successively move the pawls P i, P2, P3, etc. out of engagement from the spirally disposed teeth RI, R2, R3,;etc. carried by shaft 33 so as to permit rotation of this shaft step by step following each successive operation of the keys.

The sector shaped plate 35 as best seen in Figs. 2 and 10 is provided at its periphery with aratchet tooth 56Y disposed in engageable relation with a pin 51 carried by an arm 58 secured to the cam elements 5959Y mounted for movement as a on the reduced end portion ep of shaft 30. The cam element 59 in turn is disposed in engageable relation with an arm BIY formed with one of the arms of the plate 5 5 for actuating the latter and the pawl-like members PI, P2, P3, etc. collectively out of engageable relation from the ratchet teeth RI, R2, R3, etc. so as to prevent noise which would otherwise be generated by their frictional engagement during the counterclockwise rotation of shaft 30 as imparted by the movement of gear sector 32. by the sector shaped plate 35.

On unright supports I3 and II, best seen in Figs. 2, 4, 5, 6, 9 and 10, is mounted a shaft 69 on which is keyed a gear sector I while a handle 1| alsokeyed on this shaft is provided for moving the gear sector ID from the position shown in Figs. 2, 3, 4 and to the position shown in Fig. 6, for tensioning a motor spring I2 having one of its ends hooked to the gear sector and its other end to a pin laterally extending from an upright support I6, while actuating a pinion I3 and gear I5, keyed on a shaft I4 iournaled at both ends in upright supports 16 and 11 secured by a number of similar screws I8 to the base II).

The rotation of gear I5 is imparted to a pinion 'I'GYbest seen in Figs. 6, 8 and 9 keyed at one end on a shaft 80 supported at one end on upright support 11 and at its opposite end in an angle-shaped support 8| secured at its lower end to base III, while on the end of shaft 88 adiacent the support (H is keyed a winged governor m) and an angle gear 82 meshing with an angle gear'83 formed at one end of a spindle 84 mountedfor-free rotation in the support 8I.' To the opposite end of spindle 84 is keyed a pinion 85 for engagement with a gear rack 86 secured to a carriage 81 mounted 'forsliding movement on a shaft 88 of square cross section pivoted at both ends on upright supports-'89 and 98, best seen in Figs. 4 and 9, secured at their lower ends to the base I-Il.- Onc'a-rriage 81 is mounted an alternating current generator having a coil C, a permanent magnet GM and a plurality of vibrative elements VI, V2, V3, V4 and V5 normally held out of engageable relation from the code portion of wheels WI, W2, W3, etc. by a latching mecha. nism consisting of an arm I05, see Fig. 6, keyed on the square shaft 88, a spring-pressed pawl IDI pivoted on support 90 and an arm I02 keyed on shaft 69 provided for moving the pawl I8I out of engagement from arm I00 when the gear sector I0 and arm I82 are moved from the position shown in Figs. 2, 3, 4 and 5 to the position shown in Fig. 6 by the manual operation of arm II for permitting the movement of the generator in position, wherein the vibrative elements are'disposed in engageable relation with the code portion of wheels WI, W2, W3, etdfor transmitting the call while a cam I84 best seen in 'Figs. 8 and rent generator in position wherein the vibrative elements VI, V2, V3, V4 and V5 as above described engage With the code portion of wheels WI, W2, W3, etc., such engagement being determined by the stop or guiding bar 93, extending in line parallel to the movement of the generator and transverse of wheels WI, W2, W3, etc.

In a typical operation of the device of this invention as for transmitting the telephone call designation MH-36000, for example, as indicated by the setting of the code wheels WI, W2, W3, etc. in Fig. 1 and Figs. 12, 13, 14, 15 and 16, the manual operation of sector plate by its handle lever 34 from the position shown in Fig. 2 to the position shown in Fig. 10 operates the resetting bar through the pin 43 carried thereby extending into the slot 44 formed in the plate 35 for returning the wheels WI, W2, W3, etc. to normal nonoperated position from a previous call setting operation, while the ratchet tooth 56Y at the periphery of plate 35 engages the pin 5'! following a small angular movement of this plate from normal position to operate the arm-cam unit 58-59-598? against the tension of retractile spring 5'IY. The operation of cam 59 through its engagement with arm 6IY of bar causes this bar to move the pawl-like members PI, P2, P3, etc. in a path out of engagement from their respectively'associated teeth carried by the shaft 38 followed by the engagement of the lug L carried by sector plate 35 with the gear sector 32 for rotating the shaft 30 to normal starting position in a counter-clockwise direction, the pin 5| as shown in Fig. 10 being positioned in the track TI in the sector plate 35 so as to prevent the operation of gear sectors 2I -2Ia and thereby that of the keys KI, K2, K3, etc., through their cam portion CS abutting against the bar I9 carried by the gear sectors 2I-2Ia, the pawl-like members PI, P2, P3, etc. being-at this time in the raised position as shown in Fig. 5 where the lugs 65 carried thereby ride on the teeth RP of wheels WI, W2, W3, etc. during the return of the latter to normal non-operated positions.

The release of sector plate 35 by the operator and its consequent return movement to normal non-operated position by the tension of its retractile spring 35X is effective to return the resetting bar 45 to normal non-operated position While the reverse movement of gear sector 32 under the tension of its retractile spring 33 rotates the shaft 30 in a clockwise direction to a point wherein the tooth RI, see Fig. 11, engages the pawl-like member PI to move it downward against the tension of its retractile spring RS to a point in abuttment against the plate I I, thus preventing further rotation of shaft 38. The movement of pawl-like member PI is imparted to its respectively associated arm 21 carried by wheel WI for operatively connecting the latter with the bar 24 now in normal non-operated position as shown in Fig. 3, while the return of sector plate 35 to normal non-operated position as shown in Fig. 2 as above described is effective to position the pin 5| for movement in the track T2 upon the operation of any one of keys KI, K2, K3, etc. in this example the key K6 bearin the letters MNO 6 the first digit of the call designation above referred to. The movement of key K6 through its camming portion CS is effective to impart an arcuated movement to the bar I9 and consequently to gear sectors 2I-2Ia, 2323a and thereby to the clutching bar 24 and wheel WI but limited by the stop afforded by the engagement of the bar I9 into the recess I8 at the end of cam portion GS of key K6, thus setting the code portion of wheel WI in position for engagement with the reeds V3 and V5, of the alternating current generator for transmitting a signal corresponding to letter M which is indicated by the dial portion dp of the wheel WI appearing under the glass window in the casing IIlY as shown in Fig. 1.

In the movement of key K6 from the position shown in Fig. 3 to full operated position, the projection EX of this key as shown in Fig. 4 is effective to impart a small movement to the bar 55 for disengaging the pawl-like member PI from its ratchet tooth RI for permitting this member to return to normal under the tension of its retractile spring RS so as to disengage its clutching arm 21 from the clutching bar 24 and thereby locking the wheel WI in the operated position through the engagement of the lug 65 carried by this pawl-like member in the tooth T6 (see Fig. 5)

'of the ratchet portion of this wheel, the shaft 30 being prevented from operating while the bar 24 is out of normal position by the engagement of spring-pressed pawl 42 with one of the teeth of ratchet wheel 39, as shown in Figs. 4 and 5, until disengaged from this wheel by the pin PX when the bar 24 has reached a small distance from its normal unoperateol position.

The return movement of key K6 to normal nonoperated position under the tension of its retractile spring I5 and the consequent return movement of gear sectors 2I2Ia, 23-23a and the clutch bar 24 to normal position, permits the pawl-like member P2, Fig. 11, to move against the common stop bar SB by the tension of its retractile spring RS to a position identical to that shown by pawl PI in Fig. 6 in engageable relation with its respective operating ratchet wheel R2 on shaft 30 the operation of which is efiected by the movement of gear sector 32 following the disengagement of pawl 42 from the ratchet wheel 3 by the pin PX on the arm M of gear sector 23, rotation of shaft 30 being effective to move clutching arm 21 of wheel W2 in engaged relation with the clutching bar 24, while the operation of key K4 bearing the symbol GHI 4 the second digit of the call designation above mentioned is eifective through its cam portion CS to move the bar I9 and gear sectors 2I-2Ia and 23--23a and thereby the clutch bar 24 for rotating the wheel W2 to position where the symbols GHI of its dial portion dp appear under the glass window in casing IIIY and for engaging the reeds VI and V2 representing digit 4 and its code portion in position. This cycle of operation is repeated for each of the succeeding numbers in the call designation MEI-36000 above mentioned code wheel W3 as shown in Figs. 12, 13, l4, l5 and 16 being disposed to engage the reeds V2 and V3, the wheel W4 reeds V3 and V5, and the wheels W5 and W6 and W1, the reeds VI and V4 representing the letter O which in turn represents the number 10 as is well known in automatic telephony.

Upon the completion of the setting of the combined code indicator wheels WI, W2, W3, etc. the manual operation of handle lever 'II from the position shown in Figs. 1, and 2 to the position shown in dotted lines in Fig. 6 is effective to operate the gear sector III for tensioning its retractile spring I2 and for rotating the pinion and gear unit 'I3'I5, the pinion 'I6Y on shaft 80, the angle gears 82 and 83, the pinion 85 engaged by the gear rack 86 for moving the latter from the position shown in Fig. 8 to starting position shown in Fig. 9 wherein the latch release arm I02 keyed on shaft 69 is effective to move the'latching pawl IOI best seen in Fig. 6 out of engagement from the arm I90 carried by shaft 88 to cause the pivotal movement of this shaft under the tension of retractile spring 9| to the position against the guiding bar 33 t0 cause the engagement of the vibrative elements VI, V2, V3, etc. of the alternating current generator with the code portion of combined code indicating wheels WI, W2, W3, etc. successively upon the return of the generator to normal nonoperated position by the tension of the motor spring 12 but under control of the speed governor up on shaft 86 for transmitting signals corresponding to the call designation MH-36000. The generator i moved in position ineffective to the code elements upon the engagement of its supporting arm 81 with a cam I04 of guiding bar 93 where the latch member IBI reengages the arm I30 for holding the generator in the position shown in Figs. 2, 3, 4, 7, 10 and 11 during its operation by the manual movement of handle II as above described and the transmitter is now ready for a succeeding call setting and transmitting operation.

What is claimed is:

1. In a call transmitter, a set of key members, cams of difierent values carried by said key mambers, a set of code wheels, a clutch element actuated by the operation of said key members under control of said cams, clutch elements carried by said wheels normally disengaged from the first mentioned clutch element, a ratchet mechanism actuated by the movement of each of said key members for successively engaging said clutch elements with said first-mentioned clutch element for moving said wheels according to the values of said cams in position for setting a, call.

2. In a call transmitter, a set of key members, a, pair of pivoted gear sectors, a bar common to said key members mounted on said gear sectors, said key members having cams of different value for actuating said bar, a set of code wheels, a clutch bar mounted for movement concentric to said wheels and having gear sectors engaging the first-mentioned gear sectors, a spring actuated ratchet shaft controlled by the operation of said key members, and clutching elements actuated by the movement of said shaft for successively operatively connecting said wheels to said concentrically movable clutch bar for moving said wheels in position corresponding to the operation of said key members for setting a call.

3. In a call transmitter, a set of pivoted digit key members, cams of different values carried by said members, a plurality of code wheels, a clutching bar mounted for arcuate movement concentric to said Wheels, a gearing mechanism operatively connecting said key members to said clutching bar and actuated under control of said cams, a clutching element carried by each of said wheels, a ratchet shaft, means operable by the movement of said key members to cause the operation of said ratchet shaft for successively moving the last-mentioned clutch elements in engaged relation with said clutching bar for moving said wheels upon the operation of said key members in position for setting a call means actuated by said ratchet shaft forlocking said wheels in said position, and manually operable means for releasing and returning said wheels to normal for cancelling the call.

4. In a call transmitter, a pivoted bar, a set of key members having cam elements of different values for operating said bar, a plurality of combined code indicating wheels, a clutch bar common to said wheels, a gearing mechanism operatively connecting said pivoted bar to said clutch bar, a transfer mechanism, motor means for actuating said mechanism to cause the successive operation of said wheels under control of said key members for setting and indicating a call, and a signaling device actuated according to the setting of said wheels for transmitting the call.

5. In a call transmitter, a set of key members having cams of different values, a shaft in operative relation with said cams, a bar mounted on said shaft for concentric oscillatory movement relative thereto upon the operation of said key members, a plurality of code wheel-s, a clutch bar movable concentric to said wheels, gear sectors operated by the movement of the first-mentioned bar for actuating said clutch bar to angular movements defined by said cams, clutch elements carried by each of said wheels, a rotatable ratchet shaft having a gear keyed thereon, a gear sector, a normally tensioned motor spring attached to said gear sector for rotating said ratchet shaft, means associated with each of said wheels actuated by the movement of said ratchet shaft for successively engaging said clutch elements with said clutch bar to cause the successive movement of said wheels to positions corresponding to the cam value of said key members upon the successive operation of the latter for setting a call. a

6. In a call transmitter device, a set of key members, a plurality of code wheels, means actuated by said key members for moving said wheels in position for setting a call, an 'alternating current generator having vibrative elements, motor means for moving said generator to cause the operation of said elements by said code wheels for transmitting the call, a pivoted bar extending transverse of said wheels, a manually operated sector shaped plate for actuating said bar for returning said wheels to normal position following the transmitting of the call, means in said plate cooperating with means carried by the first-mentioned means for preventing the operation of said key members following the operation of said plate from normal non-operated position.

'7. In a call transmitter, a set of key members, a plurality of code wheels, a clutch bar, a gearing mechanism actuated by said key member for moving said clutch bar concentric to said code wheels, clutching elements carried by said wheels normally out of engaged relation from said clutch bar, a transfer mechanism for successively engaging said clutching elements with said clutch bar,

said mechanism comprising a plurality of spring retracted pawl-like members for actuating said clutching elements, a rotatable shaft having ratchet teeth disposed in staggered relation at its periphery, a motor spring for actuating said shaft to cause one of said teeth to engage one of said pawl-like members for engaging one of said clutching elements with said clutch bar for moving the corresponding code wheel in selected position upon the operation of one of said key members, stop means for limiting the movement of the operated pawl-like member and said shaft, and means actuated by the operation of the depressed key following the setting of one of said code wheels for disengaging the operated pawllike member from said ratchet shaft to cause the rotation of the latter by said motor spring for engaging the successive ratchet tooth on said shaft with its respective pawl-like member for moving its clutching element in engagement with said clutching bar for operation of its associated code wheel by the operation of a successive key.

8. In a call transmitter, a set of key members, a set of code wheels movable by the operation of said key members in position for setting a call, spring-actuated pawl-like members having means for engaging said wheels for holding the latter in said position, a pivoted plate, means carried by said plate for engaging means carried by said pawl-like members for actuating the latter collectively for releasing said code wheels, a manually operable camming mechanism for actuating said pivoted plate to effect such release, and other means actuated by the operation of said mechanism for returning said code wheels to normal from operated position following the disengagement of said code wheels by the means carried by said pawl-like members.

THOMAS L. DOWEY. 

